Here's what you do when you're a student in the Belgian town of Leuven. You don a blue plastic poncho alongside 1,499 undergraduates, all standing in line at very long table, on which is placed a bottle of Diet Coke and a Mentos. On the count of three, having raised your hood, you drop the mint in the plastic bottle, and 1,500 fountains of sticky drink erupt simultaneously. More pics below. Update: We've stuck a video up there, as well.
It's rather reminiscent of a miracle occurring during dinner in the refectory of the Order of the Blue Man Monastery (patron saint Tobias Funcke.)
The record was broken, I hope the stickiness was cleaned up from Place Ladeuzeplein, and the kids got to keep their ponchos.